1. Field of the invention
This invention relates to a sunroof device for a vehicle.
2. Description of the Related Art
A conventional sunroof device for a vehicle is disclosed in the Japanese Patent Laid Open No. 64 (1989)-22621. The sunroof device for a vehicle disclosed in the prior art comprises a guide rail fixed on a roof panel so as to be located near a circumferential portion of an opening disposed on the roof panel. The sunroof device for a vehicle comprises a movable panel supported on the guide rail through a link mechanism in order that the movable panel may open and close the opening through an operation of the link mechanism. The link mechanism includes a guide link slidably supported on the guide rail and a lift link pivotably supported on the movable panel. The lift link includes a first guide pin and a second guide pin each of which is projected in the respective sides from the lift link so as to form a triangle with a supporting axis which supports the lift link through both sides thereof. The guide link includes a first guide groove and a second guide groove each of which is formed on the respective sides of the guide link. Each of the first and second guide pins is slidably fit through the first and second guide grooves respectively so as to connect the lift link with the guide link. The engagement of the lift link and the guide link is utilized for restricting the position of the movable panel when the movable panel is moved.
Another conventional sunroof device for a vehicle is disclosed in the Japanese Patent No. 55 (1980)-15325. The sunroof device for a vehicle disclosed in the prior art comprises a guide rail fixed on a roof panel so as to be located near a circumferential portion of an opening disposed on the roof panel. The sunroof device for a vehicle comprises an movable panel supported on the guide rail through a link mechanism in order that the movable panel may open and close the opening through an operation of the link mechanism. The link mechanism includes a guide link slidably supported on the guide rail and a lift link pivotably supported on the movable panel. The lift link includes a first guide pin and a second guide pin each of which is projected from one side of the lift link so as to form a triangle with a supporting axis which supports the lift link through both sides thereof. The guide link includes a guide groove which is formed on one side of the guide link which is opposite to the lift link. Each of the first and second guide pins is slidably fit through the guide groove respectively so as to connect the lift link with the guide link. The engagement of the lift link and the guide link is utilized for restricting the position of the movable pane 1 when the movable panel is moved.
However in accordance with the former prior art as shown in FIG. 10, because the lift link B3 is supported on the guide link through respective sides of the lift link (the engagement of each of the first and second guide pins B1, B2 and the first and second guide grooves), an action line B (the line connecting the centers of gravity of the first and second guide pins B1, B2) of the force applied to the lift link B3 is rather inclined relative to the supporting axis B4 supporting the lift link B3 when the movable panel receives the force. Therefore, leverage including a long span is generated at the lift link B3. The lift link B3 is inclined because a large moment is generated at the supporting axis B4. Consequently, the lift link B3 interferes with the guide link so as to have an uneven abrasion and an operational noise.
In accordance with the latter prior art, the guide groove has to be separated into two portions or the guide groove has to be extended in the vertical direction since both of the guide pins are engaged with one guide groove. Therefore, the guide link has to be enlarged and the sunroof device for a vehicle has to be heavy in weight. In particularly, when the guide groove is extended in the vertical direction, a clearance between a passenger head and the vehicle roof is decreased.